Mold for producing cores for twyer-molds.



No. 792,992. PATENTED JUNE 20, 1905. S. A. KELLY.

MOLD FOR PRODUCING OORES FOR TWYER MOLDS.

APPLIUATION FILED MAY '7. 1904,

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MOLD FOR PRODUCING CORES FOR TWYER MOLDS.

APPLICATION FILED MAY 7. 1904.

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SA M URL A. K ELLY,

OF Pl"TSBUl{(i.

Patented June 20, 1905.

PATENT OFFICE.

PENNSYLVA NIA.

MOLD FOR PRODUCING CORE'S FOR TWYER-MOLDS.

SPECIFICATION formingpart of Letters Patent No. 792,992, dated June 20, 1905.

Application filed May '7, 1904. Serial No. 206,903.

Be it known that I, SAMUEL A. KELLY, a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented new and useful improvements in Molds for Producing Cores for 'lwycr-Molds, of which the follmving is a specilication.

This invention relates to molds for producing cores for use in tw ,'er1m)lds.

The objects of the invention are to improve and simplify the construction of such devices.

\Vith the foregoing and other minor objects in view. which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafterdescribed and claimed as a practical embodiment thereof.

In the accompanying drawings, forming part of this specification, Figure 1 is a transverse vertical section through a twyer-mold having disposed therein a core produced according to the present invention. Fig. 2 is a transverse vertical section through the improved mold of this invention. Figs. 3, at, and 5 are detail perspective views of parts of the mold.

Like reference numerals indicate corresponding parts in the different views.

As shown in Fig. 2 of the drawings, the improved mold of this invention comprises a tray 1, having an imvardlyprojecting annular flange 2, a pipe-section 3, screwed or otherwise suitably secured in the central portion of said tray, an inner shell i, preferably of conical shape, an annular plate 5, having perforations 6 therein, an outer shell 7, resting upon the plate 5, and a plurality of perforated pipes 8, extending through the perforations of the plate 5 and having their lower ends bent into parallelism with each other, said pipes being adapted to receive nuts 9 upon their lower ends.

The method of using the improved mold of this invention is as follows: The tray 1 is filled with a plastic molding material, which is smoothed off on a level with the flange 2. The inner shell-section 4 is placed upon the molding material in the tray 1, and the plate 5,with its pipes 8, is placed around said inner shell & so that the lower ends of said pipes are forced through the plastic molding material and project through the bottom of the tray .1. The outer shell 7 is placed upon the plate 5. Plastic molding material is poured into the upper end of the innershell sand outer shell 7 and tamped down in any suitable manner until the mold is completely lilled with plastic material, as indicated in Fig. 2. It will be understood by those skilled in the art to which this invention relates that the molding material usually consists of sand and flour or the like mixed into a plastic mass which is of such consistency as to preserve the shape to which it has been molded. \V hen making the core ready for molding a twyer, the nuts 9 are removed from the perforated pipes 8 and the base-plate 5, together with the pipes 8 and outer shell 7, is raised away from the tray 1. The inner shellsection' t is removed from the tray. The outer shell 7 is removed from around the core 10 and the base-plate 5 is moved away from the lower ends of the perforated pipes 8, leaving said pipes embedded in the material of the core 10. After the inner shell &, the outer shell T, and thebase-plate 5 have been removed away from the core 10 the lower ends of the pipes 8, which are still embedded in said core 10, are reinserted into the tray 1 and the nuts 9 are screwed upon the lower ends of said pipes. The tray 1 is then inverted and inserted into an ordinary form of twycr-mold 11, as shown in Fig. '1.

The pouring-gate 12, through which the molten brass or other metal enters the mold and surrounds the core 10, can be formed in any suitable manner, as by inserting a pouring-gate rod 13 into the center of the pipesection 3 before the plastic material is inserted into the tray 1.

1t will be understood that when the molten brass surrounds the twyer-core 10 the cineration of the flour or other binder contained in the molding material results in the production of gases, which are permitted to escape through the perforated pipes b. In order to prevent the pipes 8 from being brazed where they are exposed to the molten brass in the mold 11, asbestos tubing or other suitable material 14: may be placed around said pipes at that point, as will be understood by those skilled in the art. After the twyer has been molded the pipes 8 are withdrawn therefrom, and by giving the twyer a sharp rap with a hammer or other suitable implement the core 10 is caused to become pulverized and may be shaken from the twyer through the perforations left therein by the pipes 8.

Changes in the precise embodiment of invention illustrated and described may be made within the scope of the following claims without departing from the spirit of the invention or sacrificing any of its advantages.

Having thus described the invention, what is claimed is 1. In a mold for producing cores for twyermolds, an inner shell, a perforated plate surrounding said inner shell, an outer shell, a plurality of pipes extending through said plate, and means for supporting said plate and inner and outer shells during the operation of forming a core.

2. In a mold for producing cores for use in tWyer-Inolds, an inner shell, a perforated annular plate surrounding said inner shell, an

outer shell resting upon said plate, a plurality of perforated pipes extending through the perforated plate and being disposed between said inner and outer shells, and a tray adapted to receive the lower ends of said pipes.

3. In a mold for producing cores for use in twyer-molds, the combination of avtray, having an inwardly-extending annular flange, a pipe-section disposed at the center of said tray, an inner shelladapted to surround said pipesection, a perforated plate surrounding said inner shell and resting upon the annular flange of said tray, an outer shell resting upon said perforated plate, and perforated pipes extending through said perforated plate and through said tray, and having nuts on their lower ends, the upper ends of said pipes being disposed between said inner and outer shells.

In testimony whereof I affix my signature in presence of two witnesses.

SAMUEL A. KELLY.

\Vitnesses:

W. M. MOCLURE, H. H. \VUNDERLICH. 

